Lithobates pipiens formerly Rana pipiens, commonly known as the northern leopard frog, is a species of leopard frog from the true frog family, native to parts of Canada and the United States. It is the state amphibian of Minnesota and Vermont.

Leopard frog is a generic name used to refer to various species in the true frog genus Lithobates. They all have similar coloration: brown or green with spots that form a leopard pattern. They are distinguished by their distribution and behavioral, morphological, and genetic differences. The range of the various species of leopard frogs extends from the Hudson Bay in Canada, throughout the United States, throughout Mexico and other parts of Central America, and possibly the very northern section of South America.